Drought vulnerability and consequential scenarios for diverse stakeholders: The Upper Colorado River Basin
Abstract
The Colorado River is the largest river in the southwestern United States, supporting municipal, industrial, agricultural, and recreational activities worth an estimated $300 billion/year within the state of Colorado alone. While the Upper Colorado River Basin (UCRB) lies west of the Continental Divide, most of this activity takes place east of the Divide, where most of Colorado's population resides. Major diversions of water across the Divide are therefore necessary, but activities of stakeholders within the basin also need to be supported. Amidst a historic 18-year drought, there is increasing competition by diverse interests (including endangered species) for the available water. State level planning efforts in Colorado must carefully balance the competing needs as shaped by future climate extremes and manifested through the institutional framework of prior appropriation that governs water allocation in the basin.
This study assesses the vulnerabilities faced by the multiple stakeholders present in the UCRB as a result of changes in climatic extremes, demand growth, as well as in the institutional and physical infrastructure in the basin. To do so, we employ a bottom-up vulnerability assessment framework that pairs the State's own water allocation and accounting model with an exploratory modeling approach able to represent such changes. The methodology evaluates the current stream water allocation process in the Basin under a large ensemble of parameter combinations, representing potential future states of the world, and quantifies resulting user vulnerabilities. We seek to improve our understanding of the impacts of these uncertainties on the hundreds of users present in the basin, and support the State in its efforts to meet both environmental flow requirements and the needs of agricultural as well as municipal stakeholders. Our analysis reveals that stakeholders of varying sectors, water right seniority, and demand experience vastly different impacts, regarding the timing, magnitude, and frequency of shortages. Furthermore, these impacts are driven by different sets of changes and uncertainties. This work will be used to inform adaptive user- and scenario-specific conservation efforts to tackle drought in the basin by leveraging emerging patterns in the sensitivities of different stakeholders.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.H23G..01H
- Keywords:
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- 1807 Climate impacts;
- HYDROLOGY;
- 1880 Water management;
- HYDROLOGY;
- 1918 Decision analysis;
- INFORMATICS;
- 6309 Decision making under uncertainty;
- POLICY SCIENCES & PUBLIC ISSUES